Change of user agent notified

Core requirement

When content triggers a device change or an automatic user agent change, the user is notified before the change occurs.

Tests

Procedure

For each instance where the content triggers a change of device or user agent change:

Check that the change is conveyed before the chance occurs.

Expected results

#1 is true.

Key Terms

assistive technology

hardware and/or software that acts as a user agent, or along with a mainstream user agent, to provide functionality to meet the requirements of users with disabilities that go beyond those offered by mainstream user agents

Functionality provided by assistive technology includes:

alternative presentations, for example, synthesized speech or magnified content
alternative input methods, for example, voice
additional navigation or orientation mechanisms
content transformations, for example, to make tables more accessible

Assistive technologies often communicate data and messages with mainstream user agents by using and monitoring APIs.

The distinction between mainstream user agents and assistive technologies is not absolute. Many mainstream user agents provide some features to assist individuals with disabilities. The basic difference is that mainstream user agents target broad and diverse audiences that usually include people with and without disabilities. Assistive technologies target narrowly defined populations of users with specific disabilities. The assistance provided by an assistive technology is more specific and appropriate to the needs of its target users. The mainstream user agent may provide important functionality to assistive technologies like retrieving web content from program objects or parsing markup into identifiable bundles.

Assistive technologies that are important in the context of this document include the following:

screen magnifiers and other visual reading assistants, which are used by people with visual, perceptual, and physical print disabilities to change features including but not limited to text font, size, spacing, color, and synchronization with speech in order to improve the visual readability of rendered text and images
screen readers, which are used by people who are blind to read textual information through synthesized speech or braille
text-to-speech software, which is used by some people with cognitive, language, and learning disabilities to convert text into synthetic speech
speech recognition software, which may be used by people who have some physical disabilities
alternative keyboards, which are used by people with certain physical disabilities to simulate the keyboard (including alternate keyboards that use head pointers, single switches, sip/puff, and other special input devices)
alternative pointing devices, which are used by people with certain physical disabilities to simulate mouse pointing and button activations

content

information, sensory experience and interactions conveyed

user agent

any software that retrieves and presents web content for users